sys/src/cmd/sam/shell.c

   1 #include "sam.h"
   2 #include "parse.h"
   3
   4 extern  jmp_buf mainloop;
   5
   6 char    errfile[64];
   7 String  plan9cmd;       /* null terminated */
   8 Buffer  plan9buf;
   9 void    checkerrs(void);
  10
  11 int
  12 plan9(File *f, int type, String *s, int nest)
  13 {
  14         long l;
  15         int m;
  16         int pid, fd;
  17         int retcode;
  18         char *retmsg;
  19         int pipe1[2], pipe2[2];
  20
  21         if(s->s[0]==0 && plan9cmd.s[0]==0)
  22                 error(Enocmd);
  23         else if(s->s[0])
  24                 Strduplstr(&plan9cmd, s);
  25         if(downloaded){
  26                 samerr(errfile);
  27                 remove(errfile);
  28         }
  29         if(type!='!' && pipe(pipe1)==-1)
  30                 error(Epipe);
  31         if(type=='|')
  32                 snarf(f, addr.r.p1, addr.r.p2, &plan9buf, 1);
  33         if((pid=fork()) == 0){
  34                 if(downloaded){ /* also put nasty fd's into errfile */
  35                         fd = create(errfile, 1, 0666L);
  36                         if(fd < 0)
  37                                 fd = create("/dev/null", 1, 0666L);
  38                         dup(fd, 2);
  39                         close(fd);
  40                         /* 2 now points at err file */
  41                         if(type == '>')
  42                                 dup(2, 1);
  43                         else if(type=='!'){
  44                                 dup(2, 1);
  45                                 fd = open("/dev/null", 0);
  46                                 dup(fd, 0);
  47                                 close(fd);
  48                         }
  49                 }
  50                 if(type != '!') {
  51                         if(type=='<' || type=='|')
  52                                 dup(pipe1[1], 1);
  53                         else if(type == '>')
  54                                 dup(pipe1[0], 0);
  55                         close(pipe1[0]);
  56                         close(pipe1[1]);
  57                 }
  58                 if(type == '|'){
  59                         if(pipe(pipe2) == -1)
  60                                 exits("pipe");
  61                         if((pid = fork())==0){
  62                                 /*
  63                                  * It's ok if we get SIGPIPE here
  64                                  */
  65                                 close(pipe2[0]);
  66                                 io = pipe2[1];
  67                                 if(retcode=!setjmp(mainloop)){  /* assignment = */
  68                                         char *c;
  69                                         for(l = 0; l<plan9buf.nc; l+=m){
  70                                                 m = plan9buf.nc-l;
  71                                                 if(m>BLOCKSIZE-1)
  72                                                         m = BLOCKSIZE-1;
  73                                                 bufread(&plan9buf, l, genbuf, m);
  74                                                 genbuf[m] = 0;
  75                                                 c = Strtoc(tmprstr(genbuf, m+1));
  76                                                 Write(pipe2[1], c, strlen(c));
  77                                                 free(c);
  78                                         }
  79                                 }
  80                                 exits(retcode? "error" : 0);
  81                         }
  82                         if(pid==-1){
  83                                 fprint(2, "Can't fork?!\n");
  84                                 exits("fork");
  85                         }
  86                         dup(pipe2[0], 0);
  87                         close(pipe2[0]);
  88                         close(pipe2[1]);
  89                 }
  90                 if(type=='<'){
  91                         close(0);       /* so it won't read from terminal */
  92                         open("/dev/null", 0);
  93                 }
  94                 execl(SHPATH, SH, "-c", Strtoc(&plan9cmd), nil);
  95                 exits("exec");
  96         }
  97         if(pid == -1)
  98                 error(Efork);
  99         if(type=='<' || type=='|'){
 100                 int nulls;
 101                 if(downloaded && addr.r.p1 != addr.r.p2)
 102                         outTl(Hsnarflen, addr.r.p2-addr.r.p1);
 103                 snarf(f, addr.r.p1, addr.r.p2, &snarfbuf, 0);
 104                 logdelete(f, addr.r.p1, addr.r.p2);
 105                 close(pipe1[1]);
 106                 io = pipe1[0];
 107                 f->tdot.p1 = -1;
 108                 f->ndot.r.p2 = addr.r.p2+readio(f, &nulls, 0, FALSE);
 109                 f->ndot.r.p1 = addr.r.p2;
 110                 closeio((Posn)-1);
 111         }else if(type=='>'){
 112                 close(pipe1[0]);
 113                 io = pipe1[1];
 114                 bpipeok = 1;
 115                 writeio(f);
 116                 bpipeok = 0;
 117                 closeio((Posn)-1);
 118         }
 119         retmsg = waitfor(pid);
 120         if(type=='|' || type=='<')
 121                 if(retmsg[0]!=0)
 122                         warn_s(Wbadstatus, retmsg);
 123         if(downloaded)
 124                 checkerrs();
 125         if(!nest)
 126                 dprint("!\n");
 127         return retmsg[0] ? -1 : 0;
 128 }
 129
 130 void
 131 checkerrs(void)
 132 {
 133         char buf[256];
 134         int f, n, nl;
 135         char *p;
 136         long l;
 137
 138         if(statfile(errfile, 0, 0, 0, &l, 0) > 0 && l != 0){
 139                 if((f=open((char *)errfile, 0)) != -1){
 140                         if((n=read(f, buf, sizeof buf-1)) > 0){
 141                                 for(nl=0,p=buf; nl<3 && p<&buf[n]; p++)
 142                                         if(*p=='\n')
 143                                                 nl++;
 144                                 *p = 0;
 145                                 dprint("%s", buf);
 146                                 if(p-buf < l-1)
 147                                         dprint("(sam: more in %s)\n", errfile);
 148                         }
 149                         close(f);
 150                 }
 151         }else
 152                 remove((char *)errfile);
 153 }